1. Field of the Invention
The present invention relates to a reverse osmosis membrane and a method of manufacturing the same, and more particularly, to a reverse osmosis membrane including a coating layer including a copolymer of an amphoteric ionic compound and glycidyl methacrylate on the surface of the membrane and having good antifouling properties, and a method of manufacturing the same.
2. Description of the Related Art
The phenomenon of a solvent moving between two isolated solutions through a semi-permeable membrane from a solution including a lower concentration of a solute to another solution, including a higher concentration of a solute, is known as an osmotic phenomenon. In this case, the pressure acting on the solution including the higher concentration of the solute due to the movement of the solvent is known as an osmotic pressure. When external pressure, having a level higher than the osmotic pressure is applied, the solvent may move toward the solution including the lower concentration of the solute. This phenomenon is known as a reverse osmosis. Various salts and organic materials may be separated by the semi-permeable membrane by using a pressure gradient as a driving force by utilizing the principle of reverse osmosis. A reverse osmosis separation membrane using the reverse osmosis phenomenon may be used for separating molecule scale materials and removing salts from a brine or seawater to supply water available for domestic, commercial and industrial use.
Typical examples of the reverse osmosis separation membrane may include a polyamide reverse osmosis separation membrane. The polyamide reverse osmosis separation membrane may be manufactured by forming a polyamide active layer on a minute, porous support. More particularly, the minute, porous support may be formed by forming a polysulfone layer on a non-woven fabric to form the minute, porous support, forming an m-phenylenediamine (mPD) layer by dipping the minute, porous support into an aqueous mPD solution, and dipping the support into a trimesoyl chloride (TMC) organic solvent to make a contact with the mPD layer and TMC to conduct interfacial polymerization to form a polyamide layer.
Recently, in order to increase the durability and antifouling properties of a reverse osmosis membrane, for improving the performance thereof, a method of graft-copolymerizing a vinyl monomer on the surface of a polyamide active layer (U.S. Patent Publication No. 20090308804) and a method of introducing inorganic particles such as TiO2 to a polyamide active layer (U.S. Pat. No. 6,551,536), etc. have been suggested. However, according to the above-described methods, obtainable effects therefrom are trivial, or the thickness of the reverse osmosis membrane may be increased due to multiple laminated coating layers. Thus, a water purifying function may be deteriorated, and the manufacturing process may be complicated.